🔌 Energy & Fuels Overview
Brief Overview
This note covers Energy and Fuels and was created from a 22-page PDF (22-page PDF). It
dives into the different fuel types, how combustion converts chemical energy into motion,
and the mechanics of internal combustion engines.
The content focuses on fuel types, combustion processes, engine cycles, emissions, and
alternative energy options like biofuels and hydrogen.
Key Points
Overview of solid, liquid, and gas fuels and their typical uses
Detailed look at the four-stroke internal combustion cycle
Discussion of vehicle emissions and their environmental impacts
Exploration of biofuels and hydrogen as sustainable alternatives
Energy Fundamentals and Fuel Types ⛽
What is Fuel?
Fuel is a material that stores potential energy, typically in the bonds between
molecules. This stored energy is called chemical potential energy.
How chemical potential energy becomes usable energy:
Combustion — fuel reacts with oxygen to produce heat
Combustion is an exothermic reaction (produces heat)
Engines convert heat energy → mechanical energy → kinetic energy (motion)
Hydrocarbon Fuels
Hydrocarbons are molecules made only of hydrogen and carbon.
Complete combustion of hydrocarbons: C H 4 + 2O2 → C O2 + 2H2 O
Products: carbon dioxide (C O ) and water (H O)
2
2
,Fuel States and Examples
State Examples
Solid Wood, coal
Liquid Gasoline, diesel, ethanol
Gas Propane, natural gas, hydrogen
Petroleum-Based Fuels (Fossil Fuels) 🛢️
Petroleum = unprocessed crude oil OR refined products made from crude oil
Types of Petroleum-Based Fuels
Category Specific Fuels
Liquid fuels Gasoline, diesel, aviation gasoline,
aviation jet fuel, marine fuel oil
Gaseous fuels Natural gas, propane (typically stored as
liquid)
Automotive Gasoline (Mogas)
Most common vehicle fuel worldwide
Called "petrol" in some countries
Clear, flammable liquid — blend of hydrocarbons refined from crude oil
Canadian gasoline contains ~10% ethanol (biofuel) as of 2020
, Mogas hydrocarbon chains: 7–11 carbon atoms
Spark-ignition engines: Use spark plugs to ignite fuel-air mixture
Used in: Cars, trucks, vans, SUVs, boats, snowmobiles, scooters, motorcycles
Petroleum Diesel (Petrodiesel)
Second most common vehicle fuel
Liquid hydrocarbon refined from crude oil
Diesel hydrocarbon chains: 15–18 carbon atoms
Compression-ignition engines: Air is compressed until hot enough to ignite diesel fuel
(no spark plugs needed)
Characteristics:
More fuel-efficient than gasoline engines
Can produce more pollution
Diesel burns slowly and steadily due to longer hydrocarbon chains
Used in: Cars, trucks, vans, SUVs, buses, trains, boats, ferries
Aviation Fuels
Fuel Type Description Used In
Aviation Gasoline Contains tetraethyl lead Small private planes,
(Avgas) (TEL) to prevent engine vintage aircraft with piston
problems; hydrocarbon engines (spark-ignition)
chains 4–12 carbons; often
dyed for spill visibility
Aviation Jet Fuel Similar to diesel; used in Turboprop aircraft, jet
compression-ignition or aircraft, helicopters
turbine engines
Two types of aviation jet fuel:
Type Composition Properties
Jet A, JP-5, JP-8 Unleaded kerosene Standard jet fuel
, Jet B, JP-4 Blended naphtha- More volatile, less likely to
kerosene freeze — used in very cold
temperatures
Hydrocarbon chain lengths: 12–16 carbon atoms for jet fuels
Key differences from gasoline:
Higher flash point (don't ignite as easily)
Designed for turbine engines, not spark-ignition
Research area: Plant-based jet biofuel from algae and Camelina
Fuel Oils
Fuel oils = heaviest fuels from crude oil; contain longest, heaviest hydrocarbons
Type Description Uses
Distillate fuel oils Longest hydrocarbons that Trucks, trains, ships,
can still boil/condense; industrial machines
thin enough to flow easily
Residual fuel oils Heaviest leftovers after Power generation (most
distillation; very thick; must energy-dense but hardest
be blended with distillate to handle, burns least
to reduce viscosity cleanly)
Heavy Fuel Oil (HFO) / Bunker Fuel:
So thick it must be heated before burning
Requires special equipment (too large for small vehicles)
Mainly used in very large ships and power plants
Name comes from bunkers (storage containers on ships/ports)
Brief Overview
This note covers Energy and Fuels and was created from a 22-page PDF (22-page PDF). It
dives into the different fuel types, how combustion converts chemical energy into motion,
and the mechanics of internal combustion engines.
The content focuses on fuel types, combustion processes, engine cycles, emissions, and
alternative energy options like biofuels and hydrogen.
Key Points
Overview of solid, liquid, and gas fuels and their typical uses
Detailed look at the four-stroke internal combustion cycle
Discussion of vehicle emissions and their environmental impacts
Exploration of biofuels and hydrogen as sustainable alternatives
Energy Fundamentals and Fuel Types ⛽
What is Fuel?
Fuel is a material that stores potential energy, typically in the bonds between
molecules. This stored energy is called chemical potential energy.
How chemical potential energy becomes usable energy:
Combustion — fuel reacts with oxygen to produce heat
Combustion is an exothermic reaction (produces heat)
Engines convert heat energy → mechanical energy → kinetic energy (motion)
Hydrocarbon Fuels
Hydrocarbons are molecules made only of hydrogen and carbon.
Complete combustion of hydrocarbons: C H 4 + 2O2 → C O2 + 2H2 O
Products: carbon dioxide (C O ) and water (H O)
2
2
,Fuel States and Examples
State Examples
Solid Wood, coal
Liquid Gasoline, diesel, ethanol
Gas Propane, natural gas, hydrogen
Petroleum-Based Fuels (Fossil Fuels) 🛢️
Petroleum = unprocessed crude oil OR refined products made from crude oil
Types of Petroleum-Based Fuels
Category Specific Fuels
Liquid fuels Gasoline, diesel, aviation gasoline,
aviation jet fuel, marine fuel oil
Gaseous fuels Natural gas, propane (typically stored as
liquid)
Automotive Gasoline (Mogas)
Most common vehicle fuel worldwide
Called "petrol" in some countries
Clear, flammable liquid — blend of hydrocarbons refined from crude oil
Canadian gasoline contains ~10% ethanol (biofuel) as of 2020
, Mogas hydrocarbon chains: 7–11 carbon atoms
Spark-ignition engines: Use spark plugs to ignite fuel-air mixture
Used in: Cars, trucks, vans, SUVs, boats, snowmobiles, scooters, motorcycles
Petroleum Diesel (Petrodiesel)
Second most common vehicle fuel
Liquid hydrocarbon refined from crude oil
Diesel hydrocarbon chains: 15–18 carbon atoms
Compression-ignition engines: Air is compressed until hot enough to ignite diesel fuel
(no spark plugs needed)
Characteristics:
More fuel-efficient than gasoline engines
Can produce more pollution
Diesel burns slowly and steadily due to longer hydrocarbon chains
Used in: Cars, trucks, vans, SUVs, buses, trains, boats, ferries
Aviation Fuels
Fuel Type Description Used In
Aviation Gasoline Contains tetraethyl lead Small private planes,
(Avgas) (TEL) to prevent engine vintage aircraft with piston
problems; hydrocarbon engines (spark-ignition)
chains 4–12 carbons; often
dyed for spill visibility
Aviation Jet Fuel Similar to diesel; used in Turboprop aircraft, jet
compression-ignition or aircraft, helicopters
turbine engines
Two types of aviation jet fuel:
Type Composition Properties
Jet A, JP-5, JP-8 Unleaded kerosene Standard jet fuel
, Jet B, JP-4 Blended naphtha- More volatile, less likely to
kerosene freeze — used in very cold
temperatures
Hydrocarbon chain lengths: 12–16 carbon atoms for jet fuels
Key differences from gasoline:
Higher flash point (don't ignite as easily)
Designed for turbine engines, not spark-ignition
Research area: Plant-based jet biofuel from algae and Camelina
Fuel Oils
Fuel oils = heaviest fuels from crude oil; contain longest, heaviest hydrocarbons
Type Description Uses
Distillate fuel oils Longest hydrocarbons that Trucks, trains, ships,
can still boil/condense; industrial machines
thin enough to flow easily
Residual fuel oils Heaviest leftovers after Power generation (most
distillation; very thick; must energy-dense but hardest
be blended with distillate to handle, burns least
to reduce viscosity cleanly)
Heavy Fuel Oil (HFO) / Bunker Fuel:
So thick it must be heated before burning
Requires special equipment (too large for small vehicles)
Mainly used in very large ships and power plants
Name comes from bunkers (storage containers on ships/ports)
